Function AR_CASEWHEN

src/arithmetic/conditional_funcs/conditional_funcs.c:14–62

Case When * Case Value [When Option i Then Result i] Else Default end */

/* Case When
 * Case Value [When Option i Then Result i] Else Default end */
SIValue AR_CASEWHEN(SIValue *argv, int argc, void *private_data) {
	int alternatives = argc - 1;
	SIValue d = argv[argc - 1];

	if((argc % 2) == 0) {
		/* Simple form:
		 * argv[0] - Value
		 * argv[i] - Option i
		 * argv[i+1] - Result i
		 * argv[argc-1] - Default
		 *
		 * Evaluate alternatives in order, return first alternatives which
		 * is equals to Value. */
		SIValue v = argv[0];
		for(int i = 1; i < alternatives; i += 2) {
			SIValue a = argv[i];
			int disjointOrNull;
			if(SIValue_Compare(v, a, &disjointOrNull) == 0) {
				// Return Result i.
				// The value's ownership must be transferred to avoid a double free if it is an allocated value.
				SIValue retval = argv[i + 1];
				SIValue_MakeVolatile(&argv[i + 1]);
				return retval;
			}
		}
	} else {
		/* Generic form:
		 * argv[i] - Option i
		 * argv[i+1] - Result i
		 * arg[argc-1] - Default
		 *
		 * Evaluate alternatives in order, return first alternatives which
		 * is not NULL or false. */
		for(int i = 0; i < alternatives; i += 2) {
			SIValue a = argv[i];
			// Skip NULL and false options.
			if(SIValue_IsNull(a) || ((SI_TYPE(a) & T_BOOL) && SIValue_IsFalse(a))) continue;
			// The option was truthy, return the associated value.
			// The value's ownership must be transferred to avoid a double free if it is an allocated value.
			SIValue retval = argv[i + 1];
			SIValue_MakeVolatile(&argv[i + 1]);
			return retval;
		}
	}

	//Did not match against any Option return default.
	SIValue_MakeVolatile(&argv[argc - 1]);
	return d;
}

// Coalesce - return the first value which is not null. Defaults to null.
SIValue AR_COALESCE(SIValue *argv, int argc, void *private_data) {